Thinking Citizen Blog — Rivers of the US (X): The Colorado
Thinking Citizen Blog — Wednesday is Climate Change, the Environment, and Sustainability Day
Today’s Topic — Rivers of the US (X): the Colorado — dramatic canyons, water source for 40 million, seven US states plus Mexico
The Colorado is 1450 miles long and passes through 11 US National Parks. Its watershed includes seven US states plus two Mexican states (Sonora and Baja California). Once known for its reddish color from its silt, the river has changed to greenish for much of its length thanks to its 19 dams. Experts — please chime in. Correct, elaborate, elucidate.
THE COURSE OF THE RIVER: from Rocky Mountain National Park to Mexico and the Gulf of California
1. After heading southwest across the Colorado plateau, the river flows south forming the border between Arizona and California before entering Mexico where it separates the states of Baja California (west) and Sonora (east).
2. The delta has been in effect dry since the 1960s with the diversion of water for irrigation and drinking. The two largest metropolitan areas within the watershed are Las Vegas and Phoenix.
3. Water allocation is as follows: California — 27%, Colorado 23%, Arizona 17%, Utah, 10%, Mexico 9%, Wyoming, 6%, New Mexico, 5%, Nevada 2%.
NB: 85–90% of its water comes from snowmelt.
HISTORY — Hunter-gatherers, Puebloans, Navajo, Spain, Mexico, US
1. The first humans to inhabit the region were nomadic but about 2000 years ago sophisticated agricultural communities emerged (alternatively referred to as Puebloans, Anasazi, or Hisatsinom). These collapsed in the 14th century, before the arrival of the Europeans. The Navajo were their successors.
2. Then came the Spaniards such as Francisco Coronado in the 16th century in search of the Seven Cities of Gold (“Cibola”). In 1804 the region came to be the province of Alta California within the Spanish Empire which in 1822 became part of Mexico and then in 1848 under the Treaty of Guadalupe Hidalgo, part of the United States.
3. Today the river has 29 dams, basin reservoirs with capacity of four times its annual flow, and hydroelectric plants which can generate 12 billion kWh per year. Apparently, each drop of water is used 17 times per year!!!
NB: By far the most famous of the dams is the Hoover Dam, completed in 1935.
EXTINCTION, DROUGHT, RECREATION
1. Of the 49 species of native fish, 4 are extinct, and 40 in decline. 40 new species have been introduced for sports fishing — including the brown trout.
2. “The Colorado River is in its 21st year of severe drought….Lake Mead is at 40% of full capacity and Lake Powell at 48%…” When is a crisis a crisis? Odds of Lake Mead falling into “shortage” by 2025 is 80% by the latest estimates. The chances of “critically low levels” is 20%. Experts?
3. The Grand Canyon section of the river is considered “the granddaddy of rafting trips.”
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YOUR TURN
Please share the coolest thing you learned in the last week related to climate change or the environment. Or the coolest, most important thing you learned in your life related to climate change that the rest of us may have missed. Your favorite chart or table perhaps…
This is your chance to make someone’s day. Or to cement in your own mind something that you might otherwise forget. Or to think more deeply than otherwise about something dear to your heart.
